Camera capture and resolution exposed is controlled by three parameters:
--camera-width
and--camera-height
define the camera capture resolution--camera-snapshot.height
- define height for an aspect ratio scaled resolution for/snapshot
(JPEG) output - this might require rescaller and might not always work--camera-video.height
- define height for an aspect ratio scaled resolution for/video
and/webrtc
(H264) output - this might require rescaller and might not always work, this is no larger than--camera-snapshot.height
--camera-stream.height
- define height for an aspect ratio scaled resolution for/stream
(MJPEG) output - this might require rescaller and might not always work, this is no larger than--camera-video.height
The resolution scaling is following the snapshot >= video >= stream
:
snapshot
provides a high quality image for the purpose of timelapses (3Mbps-10Mbps)video
is an efficient high-quality H264 video stream (3-10Mbps)stream
is an inefficient MJPEG stream requiring significant amount of bandwidth (10-100Mbps)
libcamera-still --list-cameras
Available cameras
-----------------
0 : imx708_wide [4608x2592] (/base/soc/i2c0mux/i2c@1/imx708@1a)
Modes: 'SRGGB10_CSI2P' : 1536x864 [120.13 fps - (0, 0)/4608x2592 crop]
2304x1296 [56.03 fps - (0, 0)/4608x2592 crop]
4608x2592 [14.35 fps - (0, 0)/4608x2592 crop]
To get the best resolution for the above camera, the --camera-width
and --camera-height
needs to be configured with the native resolution of camera sensor, only then the resolution
can be downscaled.
--camera-width=2304 --camera-height=1296 --camera-snapshot.height=1080 --camera-video.height=720 --camera-stream.height=480
This will result in:
- camera will capture
2304x1296
a full sensor snapshot
be ~1920x1080video
be ~1280x720stream
be ~640x480
If the camera capture is not configured properly the result image will be cropped.
--camera-width=1920 --camera-height=1080 --camera-snapshot.height=1080 --camera-video.height=720 --camera-stream.height=480
This will result in:
- camera will capture the middle
1920x1080
from the2304x1296
snapshot
be ~1920x1080video
be ~1280x720stream
be ~640x480
You can view all available configuration parameters by adding --log-verbose
to one of the above commands, like:
tools/libcamera_camera.sh --camera-list_options ...
Or navigate to http://<ip>:8080/option
while running.
Depending on control they have to be used for camera, ISP, or JPEG or H264 codec:
# specify camera option
--camera-options=brightness=1000
# specify ISP option
--camera-isp.options=digital_gain=1000
# specify H264 option
--camera-video.options=bitrate=10000000
# specify snapshot option
--camera-snapshot.options=compression_quality=60
--camera-stream.options=compression_quality=60
You might list all available capture formats for your camera:
v4l2-ctl -d /dev/video0 --list-formats-ext
Some of them might be specified to streamer:
tools/*_camera.sh --camera-format=RG10 # Bayer 10 packed
tools/*_camera.sh --camera-format=YUYV
tools/*_camera.sh --camera-format=MJPEG
tools/*_camera.sh --camera-format=H264 # This is unstable due to h264 key frames support
It is advised to always use:
- for
libcamera
the--camera-type=libcamera --camera-format=YUYV
(better image quality) or--camera-format=YUV420
(better performance) - for
USB cameras
the--camera-type=libcamera --camera-format=MJPEG